Generation of steam



(No Model.)

0. W. BAKER.

GENERATION 0F STEAM.

Patented Nov. 27, 1894.

To all whom it may concern:

UNITED STATES PATENT OFFICE.

CHARLES WHI'IING BAKER, OF MONTOLAIR, NEW JERSEY.

GENERATION OF STEAM.

SPECIFICATION forming part of Letters Patent No. 529,997, dated November 27, 1 894.

' Application filed February 17, 1894:- Serial No. 500.536. (N0 model.)

Be it known that I, CHARLES WHITING BAKER, a citizen of the United States, residing at Montclair, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in the Generation of Steam, of which the following is a specification.

The object of my invention is to secure a greater economy than heretofore in the generation of steam, and to effect this result without any radical change in or departure from the ordinary characters or types of generators.

Experiments have shown that the ordinary tubes of generators, both fire-tube and water tube generators, can transmit a far greater proportion of heat from the fire surface to the water surface than is transmitted in any of the ordinary constructions. Various efforts have been made from time to time to utilize a greater proportion of the heat developed in the combustion of the fuel than ordinarily results, as by means for retaining the heated gases in contact with the tubes, by the adoption of tubes of peculiar construction and arranged in various ways and by departures from the ordinary forms of furnaces, butso far with the best instrumentalities employed only a fraction of the heat that should be available is utilized, and many of the means employed have resulted in such increased expense in manufacture or use or in such .serious obstruction to the draft, or inrendering the cleaning of the tubes difficult that practically but a very little benefit has ensued while in most cases the means employed could not be used in connection with boilers already constructed, or of ordinary types.

In the course of many experiments it became apparent to me that the greater portion of heat imparted to the tubular heating surface of boilers from the heated gases was received by convection or direct contact of the gases with the tubes and that but a small percentage of the heat from the great body of gases traveling within or passing the tubes, but not in direct contact therewith was conveyed to said tubes and to the water in contact therewith. Taking for an example the case of a locomotive boiler, although the tubes are of very small diameter, two inches or less, and are usually ten feet or more in length, the gases pass through them so rapidly that they pass into the smoke box and are discharged while still at a temperature far above that of the water in the boiler. The high velocity of the heated gases gives them no time to mix by the process of convection in passing through the tube and consequently while those particles in direct contact with the tube become cooled, the highly heated gases in the central portion of the tube cannot impart heat by contact with the tube except as they are displaced by the comparatively slow process of mixing due to the friction of the gas on the tube.

It has long been known that heated gases have almost no radiating power. Thus the heating surface in the fire box of a locomotive boiler, which is exposed to the directradiation from the fire, makes many times as much steam per square foot of surface exposed as does the heating surfaces in the tubes, which derive no heat from radiation and are practically heated only by contact with the rapidly moving gases.

In endeavoring to devise means by which the highly heated gases in the central portion of the tube might be made to impart their heat to it, I searched for some method of producing in the tube an equivalent tothe radiating action which occurs in the fire box of a locomotive boiler. While engaged in these studies I made the discovery that this could be effected with great simplicity and without detracting at all from the efficiency of those portions of the gases which were in direct contact with the tube surface by i'inmersing in the comparatively non-acting portions of the gases, plates of such a character and so arranged as to radiate the heat thus imparted to them directly to the tube surfaces, and that by this means it was entirely practicable to utilize a large proportion of heat which would otherwise be lost. In order to render this means of economically gener ating steam available in boilers of ordinary type, I, have provided the generators with the said radiating surfaces as fully set forth hereinafter and as illustrated in the accompanying drawings, in which Figure l is a sectional elevation of a vertical fire tube boiler provided with means for arrying out my improvement. Fig. 2 is a made and applied at an immaterial expense Cross section, enlarged, through one of the in proportion to the elfectprod uced that they tubes, illustrating the arrangement of the rain no way interfere with either the circulation diators. Fig. 3 is a vertical transverse secof the water or the direct heating action of the tion of a water tube boiler, illustrating one products of combustion,andit will be evident means of carrying out my invention in conthat in proportion as they become coated and nection with this class of steam generators. blackened by carbonaceous deposits their ra- Whatever may be the construction of the diating efficiency is increased. generator in which my improvement is car- I am aware that deflector plates have been ried out, I arrange within those channels or arranged in generators to change the direcpassages, through which the heated gases or tion of flow of the products of combustion, products of combustion must flow from the but any radiation of heat thus secured has fire place to the flue, plates of suitable form been tooinsiguificant to be of practical value which I term radiators and which are so and the possibility of a systematic arrangeplaced that they will be heated by those gases ment of such platesor other objects has never which do not come in direct contact with the been recognized. My invention differs from boiler plates and that the heat thereof will generators having such deflectors in the sysbe radiated as directly as possible to the surtematic arrangement of radiators throughout faces of said boiler plate. the generator, substantially in respect to all While the radiators may be of difierent the tubes, and in the discovery that by such forms and are arranged according to the charnleausa great increase of generating efiiciency acters of the generators, I have shown them is secured. 5 in Figs. 1 and 2 where the gases pass through I do not here claim the peculiar arrangethe boiler tubes, in the form of tubes arment of radiators illustratedin Fig. 3, in conranged concentrically within the said boiler nection with a water tube boiler as the same tubes, while in Fig. 3 where the boiler is of constitutes the subject of aseparate applicathe water tube type, I have shown them in tion for Letters Patent, Serial No. 491,043. the form of curved plates partially surround- Without limiting myself to the use of raing the tubes but with the curves of the radiators of special forms and arrangements, I diators concentric with the tubes. In any claim as my inventioncase there is no obstruction by the radiators 1. The within described improvement in ina to the passage of the products of combuscreasingtheeiiiciency of steam generators, the

tion in direct contact with the tubes or plates of the boiler, but they can thus flow in the same manner and to the same extent as would be the case if the radiators were not employed, while the said radiators become very highly heated and the heat thereof is radiated directly to the surfaces of the tubes through or over which the water passes.

Inasmuch as (as has been found) the boiler tubes normally have a heat but slightly in excess of that of the water in contact therewith while the heat of the radiator will closely approximate the maximum heat of the products of combustion the amount of heat radiated from the latter to the former will be such as to very materially increase the heating effect upon the water in the boiler and the amount of water evaporated within a given time,

As the result of numerous experiments I have ascertained thatwith certain variations, depending upon the character of the generator and the form and arrangement of the radiators an increased efficiency of from twenty to fifty per cent. is readily attainable and wholly practicable.

It will be seen that the radiators a may be arranged within the fire tubes or outside the water tubes in boilers of ordinary construction, and already in use, that they do not interfere with the ready cleaning of the boilers or tubes, that they are of a character to be same consisting in carrying the heated gases that are not in direct contact with the boiler plates or tubes in contact with plates arranged in proximity to the tubes throughout the generator in position to radiate the heat to said boiler plates or tubes, substantially as set forth.

2. The Within described improvement in generating steam thesame consisting in passing the gaseous products of combustion in :05 contact with tubes containing or surrounded by the water to be heated, and in radiating the heat of said gases from radiators heated by said gases and arranged adjacent to said tubes throughoutthe generator, substantially 1 to as set forth.

3. The combination with the tubes of a boiler, of radiating plates corresponding in outlinewith said tubes, and arranged throughout the generator adjacent thereto but out of I 15 contact therewith within the fire spaces or channels, substantially as and for the purpose set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CHARLES WI-IITING BAKER.

Witnesses:

M. N. BAKER, A. B. GILBERT. 

